Abstract
Controlled shear-wave experiments have focussed on deep crustal targets that were earlier recognized by DEKORP P-wave surveys in southern Germany (Black Forest, Upper Palatinate). A prominent P-wave reflection (“bright spot”) at 8 km depth at the KTB deep drilling site is not seen on a comparable S-wave reflection section, in contrast to deeper reflections. This behaviour can be explained either by purely compositional effects (layer with anomalously high quartz content) or by fluid accumulation (“reservoir”) in a fracture zone. A 20 km deep, 10 km long prominent P-wave reflection in the southwestern Black Forest is only partially accompanied by corresponding S-wave reflections. The influence of the physical state of the rock e.g. stress-related cracking, in addition to possible compositional variations is suggested to explain the contrasting P- and S-wave reflection strength. Seismic anisotropy of 10% magnitude, revealed by S-wave splitting in vertical seismic profiling data at the KTB to more than 4 km depth, is attributed to sub-vertically dipping and NW-striking foliation.
Published Version
Talk to us
Join us for a 30 min session where you can share your feedback and ask us any queries you have
Schedule a callDisclaimer: All third-party content on this website/platform is and will remain the property of their respective owners and is provided on "as is" basis without any warranties, express or implied. Use of third-party content does not indicate any affiliation, sponsorship with or endorsement by them. Any references to third-party content is to identify the corresponding services and shall be considered fair use under The CopyrightLaw.
